Thermoelectric generating system for vehicle

ABSTRACT

A thermoelectric generating system for a vehicle, the thermoelectric generating system includes an engine for producing power, a thermoelectric module for producing electric energy from thermal energy of an exhaust gas generated by the engine, a purifying device for purifying the exhaust gas generated by the engine, and a controller for driving the thermoelectric module when a temperature of the purifying device arrives at a predetermined operational temperature.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Korean PatentApplication No. 10-2015-0143635, filed on Oct. 14, 2015 with the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein in its entirety by reference.

TECHNICAL FIELD

The present disclosure relates to a thermoelectric generating system fora vehicle, and more particularly, to a thermoelectric generating systemfor a vehicle capable of recovering waste heat while maintaining anexhaust gas purification ability.

BACKGROUND

In general, an exhaust gas emitted from a vehicle engine containsunnecessary heat which is not useful, and is discarded in the outsideair. However, exhaust may include a large amount of heat, and mayaccount for about 30% of overall fuel consumption.

In a general gasoline or diesel engine, it is known that a quantity ofheat of about 30% of the energy of fuel supplied to the engine is usedfor normal output consumption of the engine, about 30% thereof is acooling loss, about 30% thereof is an exhaust loss, and about 10%thereof is consumed for driving other auxiliary devices. Since heat ofabout 30% is included in the exhaust gas is directly discharged anddiscarded in the air, heat loss can be reduced to enhance efficientoperations. Thus, recently, a thermoelectric generator supplyingelectricity to a vehicle using an exhaust gas of the vehicle and anexhaust heat recovery device recovering heat of an exhaust gas to heatthe interior of a vehicle have been used.

A thermoelectric element may refer to an element using a thermoelectriceffect for converting a temperature difference between both ends of adevice into electricity to thus convert thermal energy into electricenergy or allowing electricity to flow in a device to cause atemperature difference between both ends of the device to convertelectric energy into thermal energy.

However, if exhaust heat is indiscriminately recovered, a harmfulemission emitted from an engine may not be appropriately purified in acatalytic converter. That is, a catalyst cannot smoothly exhibit apurification function until the catalytic converter arrives at alight-off temperature (LOT), increasing an amount of harmful emissionsin the exhaust gas. Thus, a system for reducing harmful emissions whilealso recovering exhaust heat is desirable.

SUMMARY

The present disclosure has been made to solve the above-mentionedproblems occurring in the prior art while advantages achieved by theprior art are maintained.

An aspect of the present disclosure is to recover exhaust heat from anexhaust gas of an engine.

Another aspect of the present disclosure is to enable recovery ofexhaust heat to not affect exhaust gas purification performance.

The technical subjects of the present disclosure are not limited to theafore-said, and any other technical subjects not described herein willbe clearly understood by those skilled in the art from the embodimentsto be described hereinafter.

According to an exemplary embodiment of the present disclosure, athermoelectric generating system for a vehicle may include: an enginefor producing power; a thermoelectric module for producing electricenergy from thermal energy of an exhaust gas generated by the engine; apurifying device for purifying the exhaust gas generated in the engine;and a controller for driving the thermoelectric module when atemperature of the purifying device arrives at a predeterminedoperational temperature.

According to another exemplary embodiment of the present disclosure, athermoelectric generating system for a vehicle may include: an enginefor producing power; an exhaust manifold for allowing an exhaust gasgenerated in the engine to gather therein; a thermoelectric moduleinstalled in the exhaust manifold for producing electric energyaccording to a temperature difference; a cooling module for absorbingthermal energy from the thermoelectric module; an exhaust pipe connectedto the exhaust manifold for emitting an exhaust gas; a purifying devicedisposed in the exhaust pipe for purifying the exhaust gas; and acontroller for drive the cooling module when a temperature of thepurifying device arrives at a predetermined operational temperature.

Details of embodiments are included in detailed descriptions anddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentdisclosure will be more apparent from the following detailed descriptiontaken in conjunction with the accompanying drawings.

FIG. 1 is a block diagram illustrating relationships of a thermoelectricgenerating system for a vehicle according to an exemplary embodiment ofthe present disclosure.

FIG. 2 is a block diagram illustrating relationships between acontroller of a thermoelectric generating system for a vehicle accordingto an exemplary embodiment of the present disclosure and peripheralcomponents thereof.

DETAILED DESCRIPTION

Advantages and features of the present disclosure, and implementationmethods thereof will be clarified through following embodimentsdescribed with reference to the accompanying drawings.

The present disclosure may, however, be embodied in different forms andshould not be construed as limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the scope of the presentdisclosure to those skilled in the art. Further, the present disclosureis only defined by scopes of claims. Like reference numerals designatelike elements throughout the specification.

Hereinafter, a thermoelectric generating system for a vehicle accordingto exemplar embodiments of the present disclosure will described withreference to the accompanying drawings.

FIG. 1 is a block diagram illustrating relationships of a thermoelectricgenerating system for a vehicle according to an exemplary embodiment ofthe present disclosure, and FIG. 2 is a block diagram illustratingrelationships between a controller 40 of a thermoelectric generatingsystem for a vehicle according to an exemplary embodiment of the presentdisclosure and peripheral components thereof.

Referring to FIGS. 1 and 2, a thermoelectric generating system for avehicle according to an exemplary embodiment of the present disclosuremay include an engine 1 for generating power of a vehicle, athermoelectric module 20 for generating electric energy from thermalenergy of an exhaust gas generated in a plurality of cylinders, apurifying device 13 for purifying an exhaust gas generated in the engine1, and a controller 40 for driving the thermoelectric module 20 when atemperature of the purifying device 13 arrives at a predeterminedoperational temperature.

The engine 1 may burn fuel to generate power and emit an exhaust gas. Ahigh temperature part and a low temperature part of, or on, or near, thethermoelectric module 20 may be disposed to be spaced apart from oneanother on both sides of the thermoelectric module 20. Here, the hightemperature part may be an exhaust manifold 3 and the low temperaturepart may be a cooling module 30 (to be described hereinafter). Theoperational temperature may be a lowest temperature for the purifyingdevice 13 to perform an adequate exhaust gas purifying function.

When the temperature of the purifying device 13 arrives at theoperational temperature, the controller 40 may control an electricdevice component of the thermoelectric module 20 to allow thethermoelectric module 20 to produce electricity.

The thermoelectric generating system for a vehicle according to anexemplary embodiment of the present disclosure may include the coolingmodule 30 for absorbing thermal energy from the thermoelectric module20, and when a temperature of the exhaust gas arrives at the operationaltemperature, the controller 40 may drive the cooling module 30.

The cooling module 30 may be disposed at the low temperature part of thethermoelectric module 20. The cooling module 30 may form, or have atemperature forming, a temperature difference from the high temperaturepart, or from the temperature of the high temperature part. The coolingmodule 30 may be a watercooling type cooling module or an air coolingtype cooling module. For example, a watercooling type cooling module mayhave a cooling pump 31, and an aircooling type cooling module may have acooling fan.

The thermoelectric generating system for a vehicle according to anexemplary embodiment of the present disclosure may include an exhaustmanifold 3 to which an exhaust gas generated by a plurality of cylindersgathers and an exhaust pipe 10 connected to the exhaust manifold 3 toemit the exhaust gas. The thermoelectric module 20 may be installed inthe exhaust manifold 3.

The exhaust gas emitted from the engine 1 may flow to the exhaustmanifold 3. The thermoelectric module 20 may be installed in the exhaustmanifold 3 and configured to absorb thermal energy of the exhaust gas tothus generate electricity energy.

The thermoelectric generating system for a vehicle according to anexemplary embodiment of the present disclosure may include a temperaturesensor 11 disposed in the exhaust pipe 10 for measuring a temperature ofthe exhaust gas, and the controller 40 may perform a controllingoperation on the basis of data transmitted from the temperature sensor11.

The temperature sensor 11 may measure a temperature of the exhaust gas.The temperature of the exhaust gas may be a temperature of a catalyst.The temperature sensor 11 may measure a temperature and transmitcorresponding data to the controller 40.

The cooling module 30 may include a cooling pump 31 allowing a coolantto flow therein, and when a temperature of the exhaust gas flowing inthe exhaust pipe 10 is increased, the controller 40 may control arotational speed of the cooling pump 31 to be increased.

The cooling pump 31 may be configured to circulate a coolant therein.When a temperature of the exhaust gas is increased, the controller 40may control a revolutions per minute (RPM) of the cooling pump 31 to beincreased in order to increase a temperature gradient. By increasing theRPM of the cooling pump 31, the controller 40 may increase an efficiencyof the thermoelectric module 20.

According to an exemplary embodiment, the cooling module 30 may includea low temperature flow channel 35 heat-exchanged, or able to exchangeheat, with the thermoelectric module 20. A switching part 33 may beconfigured to open and close the low temperature flow channel 35.

When a temperature of the exhaust gas is lower than the operationaltemperature of the purifying device 13, the controller 40 may controlthe switching part 33 to close the low temperature flow channel 35, andaccordingly, a coolant may not flow to the low temperature flow channel35, stopping driving of the thermoelectric module 20 and preventinggeneration of electric energy. When a temperature of the exhaust gas isequal to or higher than the operational temperature of the purifyingdevice 13, the controller 40 may control the switching part 33 to openthe low temperature flow channel 35, and accordingly, a coolant may flowto the low temperature flow channel 35 to drive the thermoelectricmodule 20 to produce electric energy.

According to another exemplary embodiment, the cooling module 30 mayinclude the low temperature flow channel 35 heat-exchanged with, or ableto exchange heat with, the thermoelectric module 20, a bypass flowchannel 37 bypassing the low temperature flow channel 35, and theswitching part 33 opening at least one of the low temperature flowchannel 35 and the bypass flow channel 37. The switching part 33 may beconfigured to selectively open and close the low temperature flowchannel 35 and the bypass flow channel 37.

When a temperature of the exhaust gas is lower than the operationaltemperature of the purifying device 13, the controller 40 may controlthe switching part 33 to open the bypass flow channel 37 and close thelow temperature flow channel 35. Accordingly, the coolant may flowtoward the bypass flow channel 37, rather than toward the lowtemperature flow channel 35, and thus, the thermoelectric module 20 maynot be driven and thus electric energy may not be produced. When atemperature of the exhaust gas is equal to or higher than theoperational temperature of the purifying device 13, the controller 40may control the switching part 33 to close the bypass flow channel 37and open the low temperature flow channel 35. Accordingly, the coolantmay flow toward the low temperature flow channel 35 to drive thethermoelectric module 20 to produce electric energy.

The controller 40 may adjust an opening ratio of the bypass flow channel37 and the low temperature flow channel 35.

The operational temperature may be an activation temperature of acatalyst provided in the purifying device 13. The purifying device 13may include the catalyst. At a temperature equal to or higher than theactivation temperature, the catalyst may perform an exhaust gaspurification function. For example, the activation temperature of thecatalyst may be 400° C.

After the thermoelectric module 20 is driven, the controller 40 may stopdriving the thermoelectric module 20 in an idle stop state in which avehicle velocity is 0 miles per hour. In the idle stop state, eventhough the thermoelectric module 20 and the cooling module 30 may bedriven, possibly due to idle operation of the engine, the controller 40may stop driving the thermoelectric module 20 and the cooling module 30.

The thermoelectric generating system for a vehicle according to anexemplary embodiment of the present disclosure may include the engine 1generating power of a vehicle; the exhaust manifold 3 in which anexhaust gas generated by a plurality of cylinders may gather; thethermoelectric module 20 which may be attached to the exhaust manifold 3and may generate electric energy according to a temperature difference;the cooling module 30 for absorbing thermal energy from thethermoelectric module 20; the exhaust pipe 10 connected to the exhaustmanifold 3 and emitting an exhaust gas; the purifying device 13 disposedin the exhaust pipe 10 and purifying the exhaust gas; and the controller40 for driving the cooling module 30 when a temperature of the purifyingdevice 13 arrives at a predetermined operational temperature.

The present disclosure has the following advantages.

First, exhaust heat may be recovered from an exhaust gas of an engine.

Second, recovery of an exhaust gas may not affect exhaust gaspurification performance.

Advantages and effects of the present disclosure are not limited to theforegoing effects and any other technical effects not mentioned hereinmay be easily understood by a person skilled in the art from the presentdisclosure and accompanying drawings.

Hereinabove, although the present disclosure has been described withreference to exemplary embodiments and the accompanying drawings, thepresent disclosure is not limited thereto, but may be variously modifiedand altered by those skilled in the art to which the present disclosurepertains without departing from the spirit and scope of the presentdisclosure claimed in the following claims.

What is claimed is:
 1. A thermoelectric generating system for a vehicle,the thermoelectric generating system comprising: an engine configured toproduce power for the vehicle; an exhaust manifold configured to allowan exhaust gas generated in the engine to gather therein; an exhaustpipe connected to the exhaust manifold and configured to emit theexhaust gas; a purifying device disposed in the exhaust pipe andconfigured to purify the exhaust gas; a thermoelectric module installedin the exhaust manifold and configured to produce electric energyaccording to a temperature difference; a cooling module including acooling pump allowing a coolant to flow, a low temperature flow channelheat exchanged with the thermoelectric module, a bypass flow channelbypassing the low temperature flow channel, and the switching partconfigured to selectively open at least one of the low temperature flowchannel and the bypass flow channel; and a controller configured todrive the thermoelectric module when a temperature of the purifyingdevice arrives at a predetermined operational temperature, wherein whena temperature of the exhaust gas is increased, the controller increasesa rotational speed of the cooling pump.
 2. The thermoelectric generatingsystem according to claim 1, wherein when a temperature of the exhaustgas arrives at the operational temperature, the controller drives thecooling module.
 3. The thermoelectric generating system according toclaim 1, further comprising a temperature sensor disposed in the exhaustpipe and configured to measure a temperature of the exhaust gas, whereinthe controller performs a controlling operation on the basis of datatransmitted from the temperature sensor.
 4. The thermoelectricgenerating system according to claim 1, wherein when a temperature ofthe exhaust gas is equal to or higher than the operational temperature,the controller controls the switching part to open the low temperatureflow channel, and when the temperature of the exhaust gas is lower thanthe operational temperature, the controller controls the switching partto close the low temperature flow channel.
 5. The thermoelectricgenerating system according to claim 1, wherein when the temperature ofthe exhaust gas is equal to or higher than the operational temperatureof the purifying device, the controller controls the switching part toopen the low temperature flow channel and close the bypass flow channel,and when the temperature of the exhaust gas is lower than theoperational temperature of the purifying device, the controller controlsthe switching part to close the low temperature flow channel and openthe bypass flow channel.
 6. The thermoelectric generating systemaccording to claim 1, wherein the operational temperature is anactivation temperature of a catalyst provided in the purifying device.7. The thermoelectric generating system according to claim 1, whereinafter the thermoelectric module is driven, the controller stops drivingthe thermoelectric module in an idle stop state in which a vehiclevelocity is 0.